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Please correct the spelling of meteorite in the title and tags. Otherwise, searching for meteorite is much less likely to bring up your post.
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BTW I can PM the article if anyone is interested. Ya would be curious to see, but with how complete these are, I doubt a phylogenetic analysis will produce much different results. I'm wanting to understand the algorithms behind these trees - this was done via parsimony, but another method (that may subvert it) is a Bayesian approach which utilizes a similar class of algorithm we use in gravitational-wave astronomy. Interesting thought that might be worth pursuing, I would think convergence is more likely, similar to molariform posteriors in the bonnethead. The diversity of tooth forms within the genus might suggest a diversity of trophic roles? After all we're only seeing the form of one species. A modern analogue might be Carcharhinus which occupy both reefs and the open ocean, so maybe some species of Ptychodus indeed may have specialized on benthic prey.
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or maybe you? Dentistry while doing paleo research at the side doesn't sound like a bad gig to me. I definitely think you're cut out for some shark research if you ever decided to mess with that
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IMO it looks to be unlikely that these are meteorites, but here are a couple of at-home tests that might tell us something: 1. Do these stick very strongly to a magnet? 2. Scrape the rocks on unglazed ceramic, as on the underside of a plate or coffee mug. What is the color left behind?
- Today
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Just rocks.
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Okay, thank you!
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I did some searching. I believe it is Carcharodon hastalis?
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Really hard to get a good pic with that reflective surface. The first one I polished one side and it came out like a mirror almost. The others went through the tumbler. Definitely not desert varnish!
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Some of those could be ventifacts with desert varnish? Unable to judge on the "base rock". Franz Bernhard
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Definitely a tooth of some kind? I agree with the others, probably a Dolphin tooth.
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I found this shark tooth in a store. I believe it to be a Mako? My only photo. I have been here a lot, and it has been here the whole time.
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The first 3 are of the original post pic. The last 3 are of other pieces I found like it in close proximity in northern Arizona.
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Wow! Being a fan of Ptychodus sharks, this is very interesting. Thank you so much for sharing!
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I have this one.
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There were more pictures originally, if I'm not mistaken. Either that or my phone was glitching.
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Holy ####! Bombshell indeed. Mexico has some incredible Cretaceous lagerstätten that I feel will get international attention in next couple decades, as it absolutely should. The paleontology of the country is very underrated. Can't wait to see what our southern neighbors continue to discover
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Found at a local Thrift Store with newspaper clipping taped to it suggesting it is a Tyrannosaurus Rex fossil.
Randyw replied to TimWaits's topic in Fossil ID
Still a cool piece to add to the collection! How come my local thrift stores never have cool things like that? -
Piece of what I believe is reptile rib bone from Big Brook, NJ. Bone fibers are very dense - any chance it could be dinosaur?
shark57 replied to TRexEliot's topic in Fossil ID
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Lower Eagle Ford, Britton formation trip 4/23/23
jpc replied to Gcurtis45's topic in Fossil Hunting Trips
wow... that is an excellent crab haul. -
Agreed - Sea robin skull.
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Found at a local Thrift Store with newspaper clipping taped to it suggesting it is a Tyrannosaurus Rex fossil.
TimWaits replied to TimWaits's topic in Fossil ID
Thanks for the information. So it is a fossil but essentially a paperweight? -
I think it might be part of a sea robin skull.
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Hello all! I'm hoping to get a bit more information on this "tooth" I found in the surf at Panama City Beach, Florida, Bay County. I was literally telling my wife that I really would like to find a shark's tooth on the beach and then found this about 5 minutes later. It doesn't look like any of the shark's teeth I have ever seen elsewhere and doesn't seem to have any edge serations. I'm just hoping to get some idea as to: 1. Is this an older or fossilized tooth? 2. What shark or other animal is it likely from? Not well visualized from the photos (best seen on pic #4 and #6), but this tooth has at least two foramina that extend longitudinally from the top down to the lateral protrusions near the point or apex. You can see their origins along the upper mounting edge. If it really is a tooth, I'm curious as to what the purpose of the foramina would be? Perhaps sensory nerve canals of some sort? Venom injection ports?? Interesting structure either way... I'm a total novice who just happened to find this on the beach a few days ago. So, any information anyone can provide is definitely welcome! I hope the photos are satisfactory, but please let me know if I need to redo anything. This is the best resolution I can do with my phone. Thank you!! MrPisky
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Now that is a bombshell article! Wonder what other Ptychodus experts think about these conclusions because this turns things completely upside down. This reminds me about the time I had first learned of Ptychocorax, the Anacoracid (Lamniformes) that has typical Squalicorax teeth in the front and Ptychodus-like teeth in the back. I wonder if some day they will determine that Ptychodontidae was an early offshoot of Anacoracidae. That family already seems to have a head start for high bite force so maybe to bridge that gap is not as difficult as we previously thought. The stuff about them being high speed swimmers that ate turtles and ammonites instead of benthic animals is also interesting. It throws a wrench into the traditional explanation for why oysters and clams of the Late Cretaceous got such big shells (higher durophagus predation from Ptychodus namely). Thanks for sharing this
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